gaboshlib/g_calc.sh

@@ -1,34 +1,66 @@
 function g_calc {
 
-  # function for calculating via bc running in the background (much faster then starting bc every time)
-  # $g_fd_bc_in $fd_bc_out have to be global
-
   unset g_calc_result
 
-  # check if bc is already running
+  local g_calc_jobs g_rnd 
-  if [[ -z "$g_fd_bc_in" || -z "$g_fd_bc_out" ]]
+  local g_bc_running=true
+  mapfile -t g_calc_jobs < <(jobs -r)
+  g_calc_jobs_v=${g_calc_jobs[*]}
+  [[ $g_calc_jobs_v =~ bc  ]] || unset g_bc_running
+
+  # Use bc in backround for multiple bc's running much faster
+  if [ -z "${g_bc_running}" ]
   then
-    local bc_input="$g_tmp/$$-g_bc_input"
+
-    local bc_output="$g_tmp/$$-g_bc_output"
+    g_kill_all_background_jobs bc-ql
-    # create fifo pipe
+    g_kill_all_background_jobs sed
-    [ -p "$bc_input" ] || mkfifo "$bc_input"
+
-    [ -p "$bc_output" ] || mkfifo "$bc_output"
+    g_rnd=$$
-    # run bc in background und switch i/o to pipes
+    mkdir -p ${g_tmp}/${g_rnd}
-    bc -ql < "$bc_input" > "$bc_output" 2>&1 &
+    [ -p ${g_tmp}/${g_rnd}/bc-in ] || mkfifo ${g_tmp}/${g_rnd}/bc-in
-    # store in filedescriptiors
+    [ -p ${g_tmp}/${g_rnd}/bc-out ] || mkfifo ${g_tmp}/${g_rnd}/bc-out
-    exec {g_fd_bc_in}> "$bc_input"
+    [ -p ${g_tmp}/${g_rnd}/bc-sed-in ] || mkfifo ${g_tmp}/${g_rnd}/bc-sed-in
-    exec {g_fd_bc_out}< "$bc_output"
+    [ -p ${g_tmp}/${g_rnd}/bc-sed-out ] || mkfifo ${g_tmp}/${g_rnd}/bc-sed-out
-  fi
+
-  # send calculation and read result
+    # bc stream channel
-  echo "$1" >&${g_fd_bc_in}
+    { bc -ql <${g_tmp}/${g_rnd}/bc-in 2>&1 >${g_tmp}/${g_rnd}/bc-out & } 2>/dev/null
-  read -u ${g_fd_bc_out} g_calc_result
+    exec 3>${g_tmp}/${g_rnd}/bc-in 4<${g_tmp}/${g_rnd}/bc-out
-  g_calc_result=${g_calc_result//-./-0.}
+
-  g_calc_result=${g_calc_result//./0.}
+    # sed stream channel
-  if ! g_num_valid_number $g_calc_result
+    { sed -su 's/^\./0./; s/^-\./-0./' <${g_tmp}/${g_rnd}/bc-sed-in >${g_tmp}/${g_rnd}/bc-sed-out & } 2>/dev/null
+    exec 5>${g_tmp}/${g_rnd}/bc-sed-in 6<${g_tmp}/${g_rnd}/bc-sed-out
+
+    g_bc_running="true"
+  fi 
+
+  # do bc
+  echo "scale=8; $@" >&3
+  local g_bc_out
+  if ! read -t 0.1 g_bc_out <&4
   then
-    echo "${FUNCNAME} $@" 1>&2
+    g_traceback "$@"
-    unset g_calc_result
+    ( exec 3<&- ) 2>/dev/null
+    ( exec 4<&- ) 2>/dev/null
+    ( exec 5<&- ) 2>/dev/null
+    ( exec 6<&- ) 2>/dev/null
+    #unset g_bc_running
+    return 1
+  fi 
+
+  # do sed
+  echo ${g_bc_out} >&5
+  local g_sed_out
+  if ! read -t 0.1 g_sed_out <&6
+  then
+    g_traceback "$@"
+    ( exec 3<&- ) 2>/dev/null
+    ( exec 4<&- ) 2>/dev/null
+    ( exec 5<&- ) 2>/dev/null
+    ( exec 6<&- ) 2>/dev/null
+    #unset g_bc_running
     return 1
   fi
-}
 
+  # store result
+  g_calc_result=$g_sed_out
+}